Electrical systems and infrastructure might emit electromagnetic radiation. This radiation is considered hazardous to human beings.
Standards define the maximum allowable daily radiation as around 2-4 miligauss. In many electrical and infrastructure systems, the radiation level greatly exceeds the permissible amount. In electrical distribution boards, high tension transformers, and electric cables, for example, the radiation level can reach hundreds of miligauss at close range. As the distance from this electrical infrastructure increases, the level of hazardous radiation decreases approximately in proportion to the square of the distance. Human beings within range of the danger do not feel and are not aware of the radiation and the resulting health hazard.
The current solutions include testing electromagnetism by an authorized examiner of the electromagnetic fields at every point where a person is located. These tests are conducted periodically in places that are aware of the testing. The problem with this method is that by the time a hazardous level of radiation is detected, it is liable to be too late for a person who has been exposed to it. It is also difficult to trace the source of the radiation.
The purpose of the current invention is to solve these problems.
A residual-current device (RCD) includes a sensing coil being a differential current transformer which surrounds (but is not electrically connected to) the live and neutral conductors. In normal operation, all the current down the live conductor returns up the neutral conductor. The currents in the two conductors are therefore equal and opposite, thus the radiation of both, cancel each other.
For a RCD used with three-phase power, all three live conductors and the return conductor must pass through the current transformer.
However, the RCD is not intended to solve the problems of the system, but rather to cut out the supply once detecting a leak of a certain consumer.
Further, the RCD is designed for detecting electric flow crossing a single cable only. The RCD is used for detecting high intensity dripping, and where the resistance of the ground is high. The RCD is designed to prevent electrocution, not electromagnetic radiation.